关键词: 丘陵赤红壤, 蒸散量, 计算模型, 季节性变化

Abstract: With a pot culture of simulated mercury (Hg) and cadmium (Cd)polluted wetland,this paper studied the capability of Arundo donax in accumulating these heavy metals,and their distribution in the plant.The results showed that after grown in a 101 mg·kg^-1 Hgpolluted wetland for 8 months,the Hg-concentrating capability of Arundo donaxwas in order of root> stem> leaf, and the Hg concentration in its aboveground parts was 200±20 mg·kg^-1(DW); while in the case of 115 mg·kg^-1 Cdpollution,the Cd-concentrating capability was in order of leaf>root>stem,and the Cd concentration in leaf was 160±26 mg·kg^-1(DW).The heavy metals concentration in Arundo donax organs increased with its growth time,being 30%～50% higher for 8 months than for 4 months.The BCF (Bio-concentration factor) decreased with increasing heavy metals concentration.In polluted wetland,the BCFs of Hg by the leaf and stem were 1.9 and 2.1,and those of Cd were 1.5 and 0.3, respectively; while in unpolluted wetland,the concentration of Hg and Cd was 6.8 and 8.5mg·kg^-1,the BCFs of Hg by the leaf and stem were 6.8 and 12.2, and those of Cd were 7.0 and 2.7,respectively.It was indicated that Arundo donax not only had the characters of large biomass,exuberant root,and good adaptability,but also exhibited high tolerance and concentrating capability to Cd and Hg.

Key words: Latored soil in hills, Evapotranspiration, Calculation model, Seasonal change